Fixation systems can be used in orthopedic surgery to align and/or fix a desired relationship between two or more bones or bone fragments. For example, in spinal surgery, spinal fixation systems can be used to align and/or fix a desired relationship between vertebral bodies. Such devices typically include a spinal fixation element, such as a relatively rigid fixation rod, that is coupled to the vertebrae by attaching the element to various anchoring devices, such as hooks, bolts, wires, or screws. The fixation element can have a predetermined or adjustable contour selected based on the desired correction or fixation. Once installed, the fixation element holds the vertebrae in a desired spatial relationship, either until desired healing or spinal fusion has taken place, or for some other period of time.
There are a number of instances in which it can be desirable to couple multiple spinal fixation elements to each other. For example, various aspects of the patient's anatomy, the surgical technique used, and/or the desired correction can require multiple spinal rods to be coupled to one another. By way of further example, there can be a desire in some revision surgeries to extend a previously-installed construct to additional vertebral levels by coupling a newly-installed spinal rod to a previously-installed rod. As yet another example, coupling multiple rods to one another can improve the overall strength and stability of an implanted construct.
Minimally-invasive surgical techniques have been developed to facilitate installation of spinal fixation systems via one or more percutaneous working channels, thereby reducing patient trauma and recovery time. These techniques, however, are often not well-suited for installing multiple fixation elements which are to be coupled to one another, or for coupling a new fixation element to a previously-installed construct during revision surgery. Even in open surgery, existing systems for coupling multiple fixation elements to one another can be cumbersome and difficult to use. Accordingly, a need exists for improved spinal connectors and related methods.